Scalable computing systems comprise a set of computers configured to process computing jobs. Computers may be added to the system or removed from the system as the demand changes. The resource load on a scalable computing system for processing database system jobs can be extremely spiky, as large jobs come and go. When a request for a large job is received, preparing the system to perform the large job can take a great deal of time, as additional computers are brought up and data for processing transferred to them. This slowdown lowers the overall efficiency of the scalable computing system and its ability to process large jobs on demand.